'/%3E%3C/svg%3E)
Hover image to zoom
 --%3E %3Csvg version='1.1' id='Fill' xmlns='http://www.w3.org/2000/svg' xmlns:xlink='http://www.w3.org/1999/xlink' x='0px' y='0px' viewBox='0 0 100 100' enable-background='new 0 0 100 100' xml:space='preserve'%3E %3Cpath fill='%23F15C02' d='M79.44,0.95H20.56C9.78,0.95,0.95,9.78,0.95,20.56v58.87c0,10.79,8.82,19.61,19.61,19.61h58.87 c10.79,0,19.61-8.83,19.61-19.61V20.56C99.05,9.78,90.22,0.95,79.44,0.95z M65.38,58.24l9.38,29.58L49.69,69.78L24.5,87.82 l9.34-29.6L8.8,39.6l30.73-0.17c0,0,6.98-19.61,10-28.93c0.54,1.36,9.88,29.1,9.88,29.1H91.2L65.38,58.24z'/%3E %3C/svg%3E){kind=small}
Hover image to zoom
' fill='%23F15C02' d='M49 0C21.938 0 0 21.938 0 49s21.938 49 49 49 49-21.938 49-49S76.062 0 49 0m0 82.709a7.54 7.54 0 1 1 0-15.08 7.54 7.54 0 0 1 0 15.08m7.54-28.412a7.541 7.541 0 0 1-15.08 0V22.831a7.54 7.54 0 0 1 15.08 0v31.466z'/%3E%3C/svg%3E)
143-381 has been discontinued
Discontinued May 6, 2022
This product was discontinued by the manufacturer.
MANUALS (4)
Direct Replacement:
THERM-X-TROL ST-25V Expansion Tank (10.3 Gallon Volume)
Product Highlights
–
10.3 Gallons
5 Year Warranty
100 MAX PSI
19.25"
15-3/8" Diameter
200°F Max Temp
Description
–
Note: This is designed for closed, low temperature systems
with a maximum operating temperature of 200° F. The product can be
used in glycol applications and features a plastic liner that is compatible
with barrier and non-barrier tubing.
Specifications
Tank Volume: 10.3 gallons
Max. Accept. Volume: 10.3 gallons
Height: 19"
Diameter: 15"
System Connection: 3/4" NPTF
Shipping Weight: 23 lbs.
Performance Data
Utilizes internal plastic liner for corrosion resistance in system with high oxygen content or non-barrier tubing
Pre-charge should be adjusted to equal system fill pressure
Brass fitting polypropyline liner for corrosion resistance
Maximum working pressure: 150 psig
Maximum operating temperature: 200 degrees F
Specifications
Tank Volume: 10.3 gallons
Max. Accept. Volume: 10.3 gallons
Height: 19"
Diameter: 15"
System Connection: 3/4" NPTF
Shipping Weight: 23 lbs.
Performance Data
Utilizes internal plastic liner for corrosion resistance in system with high oxygen content or non-barrier tubing
Pre-charge should be adjusted to equal system fill pressure
Brass fitting polypropyline liner for corrosion resistance
Maximum working pressure: 150 psig
Maximum operating temperature: 200 degrees F
Specs
–
| Tank Volume: | 10.3 Gallons |
|---|---|
| Height: | 19.25" |
| Application: | Heating |
| Max Pressure (PSI): | 100 |
| Diameter (Inches): | 15-3/8" |
| Max Accepted Volume: | 10.3 Gallons |
| Max Temp (F): | 200°F |
| Precharged PSI: | 12 psi |
| Thread Size: | 3/4" |
| Thread Type: | Female |
| Warranty: | 5 Year |
Questions?
Speak with a real person who will go out of the way to help!
Call or text 888-757-4774
Monday – Thursday
8am–7:45pm
Friday
9am–7:45pm
Saturday – Sunday
9am–5:45pm
Need help calculating?
Use Our CalculatorProduct Reviews
4.75 out of 4 reviews
100% would recommend this product
5 star
75%
4 star
25%
3 star
0%
2 star
0%
1 star
0%
Showing 1-4 of 4 reviews
Solved all my problems
Before installing this tank I had a 4.4 gallon and it couldn't mantaine the pressure in my boiler system. Now after a little of pipe reworking problem solved
Dan da man
Leonia nj
6 years ago
Verified Buyer
Was this review helpful to you?
Exactly what I needed
Arrived three days after ordering online
John the fixer
Milwaukee
10 years ago
Verified Buyer
Was this review helpful to you?
It worked
It worked
floor mounted exp pank
DAC P&H
Closter NJ
10 years ago
Verified Buyer
Was this review helpful to you?
 --%3E %3Csvg version='1.1' id='With-RB' xmlns='http://www.w3.org/2000/svg' xmlns:xlink='http://www.w3.org/1999/xlink' x='0px' y='0px' viewBox='0 0 100 100' enable-background='new 0 0 100 100' xml:space='preserve'%3E %3Cpath fill='%23FBC8B4' d='M79.44,0.95H20.56C9.78,0.95,0.95,9.78,0.95,20.56v58.87c0,10.79,8.82,19.61,19.61,19.61h58.87 c10.79,0,19.61-8.83,19.61-19.61V20.56C99.05,9.78,90.22,0.95,79.44,0.95z M65.38,58.24l9.38,29.58L49.69,69.78L24.5,87.82 l9.34-29.6L8.8,39.6l30.73-0.17c0,0,6.98-19.61,10-28.93c0.54,1.36,9.88,29.1,9.88,29.1H91.2L65.38,58.24z'/%3E %3C/svg%3E){kind=small}
Different Mounting Than Shown
This is a floor mount model. It is smaller than your normal well tank, however because of it's size, you probably wouldn't want to hang it anyways. Mine came colored red.
Outdoor Boiler
Elliotsburg, PA
14 years ago
Verified Buyer
Was this review helpful to you?
Product Q&A
1 Question1 Question
Q: i have a furnace that has a amtrol model 30 expantion tank but the plumbing to my radiators start out at3" BLACK PIPE, THE PRESSURE RELIEF VALVE CONTINUES TO EMPTY EVERYTIME THE FURNACE STARTS UP FROM COLD OR BEING IDLE FOR A LITTLE WHILE AFTER BEING CHANGED BY MY HEATING PROFESSIONALS. THE FURNACE ALSO WHEN STARTING UP WITH THOSE SYMPTOMS RUNS FOR ABOUT A MINUTE THEN SHUTS OFF,AGAIN TURNS ON THEN OFF UNTIL IT BRINGS THE BOILER UP TO TEMP UNLOADS ITS WATER THEN RUNS FINE. COULD THIS BE BECAUSE THE EXPANTION TANK IS TO SMALL
Asked by DAVE 16 years ago
Add your answer
Verified Reply- PexSupply StaffYes, the tank can be too small or the tank can be bad (water logged) and in need of replacement.
Was this review helpful to you?